The time when the exported range should begin. Time in seconds since epoch (1970-01-01) is required. Negative numbers are relative to the current time. By default one day worth of data will be printed. See also AT-STYLE TIME SPECIFICATION section in the rrdfetch documentation for a detailed explanation on how to specify time.

Address of the rrdcached daemon. If specified, a "flush" command is sent to the server before reading the RRD files. This allows rrdtool to return fresh data even if the daemon is configured to cache values for a long time. For a list of accepted formats, see the -l option in the rrdcached manual.

The output is enclosed in an xport element and contains two blocks. The first block is enclosed by a meta element and contains some meta data. The second block is enclosed by a data element and contains the data rows.